By a phenol oxidizing enzyme is meant an enzyme which by using hydrogen peroxide or molecular oxygen, is capable of oxidizing organic compounds containing phenolic groups. Examples of such enzymes are peroxidases and oxidases.
It has earlier been found that coloured substances leached from dyed fabrics could be bleached by means of a phenol oxidizing enzyme. The use of peroxidases or oxidases for inhibiting dye transfer in this way is described in WO 91/05839.
Certain oxidizable substances, e.g., metal ions and phenolic compounds such as 7-hydroxycoumarin, vanillin, and p-hydroxybenzenesulfonate, have been described as accelerators or enhancing agents able to enhance enzymatic bleaching reactions (cf. e.g. WO 92/18683, WO 92/18687, and Kato M and Shimizu S, Plant Cell Physiol. 1985 26 (7), pp. 1291-1301 (cf. Table 1 in particular)). In WO 94/12621 other types of enhancing agents are disclosed, e.g., phenothiazines and phenoxazines.
It is the object of this invention to provide a new group of enhancing agents which are effective for enhancing phenol oxidizing enzymes.